Assume that IQ scores are normally distributed, with a mean $μ$ $mu$ of 100 and standard deviation $σ$ $sigma$ of 15. What is the probability that a randomly selected person has an IQ score greater than 120?

Question

10042 views around the world

You can reuse this answer
Creative Commons License

Answer 1 · 2015-02-18T15:25:14

$0.0912 or 9.12 %$ $0.0912 or 9.12%$

I did this on a TI-83 plus:

(2nd)-Distr
Choose normalcdf from the menu

Fill in:

$(120, 10^{99}, 100, 15)$ $(120,10^99,100,15)$ and Enter

$120 =$ $120=$ lower bound,
$10^{99} =$ $10^99=$ upper bound,
$100 =$ $100=$ mean $μ$ $mu$
$15 =$ $15=$ standard deviation $σ$ $sigma$

Assume that IQ scores are normally distributed, with a mean μmu of 100 and standard deviation σsigma of 15. What is the probability that a randomly selected person has an IQ score greater than 120?